[ female announcer ] certain genetic factors and some medicines, such as prilosec reduce the effect of plavix leaving you at greater risk for heart attack and stroke. your doctor may use genetic sts to determine treatment. don't stop taking plavix without talking to your doctor as your risk of heart attack or stroke may increase. people with stomach ulcers or conditions that cause bleeding should not use plavix. taking plavix alone or with some other medicines, including aspirin, may increase bleeding risk, so tell your doctor when planning surgery. tell your doctor all medicines you take, including aspirin, especially if you've had a stroke. if fever, unexplained weakness or confusion develops, tell your doctor promptly. these may be signs of ttp, a rare but potentially life-threatening condition, reported sometimes less than 2 weeks after starting plavix. other rare but serious side effects may occur.